Stabilized parasiticidal composition



Patented July 19,1938 meters UNITED STATES PATENT No Drawing. Application January 6, 1936, Serial No. 57,780

11 Claims. (01. 167-30) The present invention relates to thio-diarylform showing the SH group, are particuamine parasiticidal compositions stabilized by the larly eflicient in my invention.

addition thereto of certain sulfur compounds de- Among the organic sulfur compounds I obtain rived from sulfur acids of an oxidation stage very useful stabilization with, for instance, merlower than sulfuric acid. captans, such as mercaptobenzothiazole, octyl '5 Thio-diarylamine parasiticides readilydeteriomercaptan, lauryl mercaptan, thiobetanaph rate when exposed to atmospheric conditions and thol, thiourea, thioamides, diphenyl-thiourea, etc. gradually lose their toxicity and efficiency. It Among the stable, reducing derivatives of the was, for instance, found that a thio-diphenyllower sulfur-oxygen acids, I found that their amine insecticide lost 60% of its activity in killing ammonia, alkali-metal, amine, or other metal 10 insects when exposed in the open airfive days. salts are readily available and useful in my in- I have found that parasiticidal compositions, vention.

based on thio-diarylamines which contain minor They are stable under the conditions of examounts, for instance, from 1 to 10% figured on posure to the atmosphere at which they are used the thio-diarylamine present, of a stable, reducaccording to my invention. Besides these salts, l5 ing derivative of a lower sulfur acid, do not lose their aldehyde and ketone derivatives are liketheir parasiticidal efiiciency in the same degree wise very efficient for stabilizing thio-diarylaminc when exposed to atmospheric conditions. parasiticides. Among the numerous compounds In generalIprefer to use neutral or only slightof this type which I contemplate admixing with ly basic, 1. e., non-acidic compounds or derivathio-diarylamine compositions I wish to list the tives of lower sulfur acid compounds which I adfollowing: sodium or potassium sulfites; ammonimix with the thio-diarylamine to stabilize the um, sodium, potassium thiosulfates; ammonium, latters toxicity. sodium, potassium, zinc hydrosulfites (in this The lower sulfur acids, the derivatives of which connection I use the expression hydro sulfites in 35 are useful in my invention, are mainly sulfurous preference to hypo sulfites, in view of the fact 2' acid, E803, thio-sulfurous acid H2S2O7, hydrothat this latter expression is still used, particusulfurous acid H2S2O4, the polythionic acids, hylarly in commercial practice, to designate thicdrogen sulfid, etc. The free acids themselves are sulfates M2S2O7, and this double use might lead mostly unstable or volatile and it is only theirto confusion); the aldehyde derivatives of the stable derivatives which display a distinct reduchydrosulfites, for instance, sodium or zinc for 3G ing action in aqueous media which are contemmaldehyde-sulfoxylates; and the alkali metal plated for use as stabilizing agents for thio-dipolythionates. arylamine parasiticides. The above includes substances of this type Another common characteristic of these sulfur which are commonly available commercially, but compounds is their reducing action in aqueous it will be understood that my invention is not 3.3 media. This reducing action is, for example, limited to the use of the commercially available shown by their action on quinonic dyestuffs which substances. are transformed into leuco-compounds by th it was found that thio-diarylamine parasitiaction of such sulfur compounds, methylene blue cides become greenish bluish 011 8111308111? 40 bejngadyest fi which is easily reducedtoa'leucm the atmosphere, and that with this change of to compound by thesulfmcompounds f my invem color towards the short wave length end of the t Broadly Speaking, these Sulfur compounds spectrum, the toxicity correspondingly diminare also capable of acting upon discolored thim lshes. When th s discoloration is prevented or diphenylamine which for instance, has been wheirthe thio-diphenylamine is treated with a transformed by oxidation into a green compound f .sulfur compmtnd desqnbeq 45 to restore its original color. 252 232? fi ggg gg ember The derivatives of hydrogen sulfid which are sufliciently stable, have reducing properties and the Peruse of my mv-emlon I {minutely mix a minor amount, for instance, mom 1 to are available for the stabilization of thio-diphen- 107 of a reducin sulfur d t y a e parasiticides, include water soluble sula g compoun wlth he thlo" v0 diarylamine and when sprayed on vegetation it d u h as the a k metal, barium, 6110- will be found that the composition remains eflicient without discoloration for a much longer period than a parasiticide containing no such in- For most purposes, i1 prefides, but I found that organic compounds containing the sulfhydryl, SH group, or organic 55 sulfur compounds which can exist in a tautomeric activation inhibitor.

fer to use 8. though soluble compounds which, on evaporation of the water of the spray, will deposit upon the particles of the insoluble thio-diarylamine.

A very simple and eflicient manner of testing a given sulfur compound for its availability as an atmospheric inactivation inhibitor for thio-diarylamine parasiticides is as follows:

A few drops of an aqueous ferric chloride solution is added to a solution of thio-diphenylamine in acetone: the solution turns immediately green. When the acetone solution contains a small amount of a reducing sulfur compound as described herein, no such green coloration develops.

parasiticides.

In this test I found, for instance, that the discoloration by ferric chloride of a mercaptan, lauryl mercaptan, thio-urea, thio-beta-naphthol, diphenyl--thiourea, other substituted thioureas, a thioamide, a formaldehyde sulfoxylate, sodium suifite, sodium thiosulfate, sodium hydrosulfite, etc.

These compounds have also been found to inhibit the atmospheric inactivation of thio-diphenylamine and other thi-diarylamine parasiticides.

in which R. and R are aromatic nuclei.

The proto type of these compounds is thio-diphenylamine, which is produced, for instance, by heating diphenylamine with sulfur of a catalyst, such as aluminum chloride, ferric chloride, iodine, etc.

Other members of the novel group of insecticides according to my invention are the thio compounds obtained by the action of sulfur upon diarylamines such as, for instance, those obtained from phenyi-alpha-naphthyl amine which presumably has the formula or from phenyl-beta-naphthylamine,

di-alpha-naphthylamine, di-beta-naphthylamine, di-biphenylamine, N, N-diphenyl-p-phenylenediamine, N, N-di-alpha-naphthyl-para phenylene-diamine,

N, N-dibiphenyl-metaphenylene-diamine, N, N-dipheny-metaphenylene-diamine, N, N-di-phenyl-benzidine, p, p'-di-(pheny1-amino) di-phenylamine.

The thio derivatives obtained from these diarylamines are all heterocyclic nucleus in which R and R which two adjac forming the bet ring.

Some of the hydrogen atoms to R and R ogen, which do pounds.

These parasitici aqueous suspensi monly spreading, agents, or as dry substances, such and others.

my novel inactivation inhi lowing:

characterized nitro, amine, alkoxy not impart water s as talc, fora are aromatic ent carbon atoms erocyclic carbon-nitroaen-sulfur dal compositions are on as sprayswhich emulsifying, dusts in admixture with inert miniferous powders or aryloxy groups, olubility to the comby containing the nuclei in each of ake part in used in include comor wetting out Apples were sprayed with a parasiticidal composition of three pounds thio-diphenylamin in wetting agent, a

water which contained 11 another set 1 was added to the spray. In

e apples were infected with codbelow:

Per cent control 1. A parasiticid thio-diarylamine 2. A parasiticidal composition comprising a thio-diarylamine as the active parasiticidal ingredient stabilized by a stable derivative of a sulfur acid of an oxidation stage lower than that of sulfuric acid, said derivative having the property of inhibiting the discoloration toward green when present in an acetone solution of thio-diphenylamlne on addition thereto of ferric chloride.

3. A parasiticidal composition comprising a thio-diarylamine as the active parasiticidal ingredient stabilized by a non-acidic, stable, reducing derivative of a lower sulfur-oxygen acid.

4. A parasiticidal composition comprising a thio-diphenylamine as the active parasiticidal ingredient stabilized. by a sulfhydryi compound which has reducing properties and is able to react with thio-diphenylamine which has become of a green color by the action of atmospheric exposure to restore its color.

5. A parasiticidal composition comprising a thio-diphenylamine as the active parasiticidal in gredient stabilized by a stable organic compound having reducing properties and containing a sulfur-containing group in which an -SH group is at least reactively available.

6. A parasiticidal composition comprising a thio-diarylamine as the active parasiticidal ingredient stabilized by a stable reducing derivative of a sulfur acid of an oxidation stage lower than that of sulfuric acid containing a sulfhydryl roup.

- '7. A parasiticidal composition comprising a thio-diarylamine as the active parasiticidal ingredient stabilized by a stable reducing derivative of a sulfur acid of an oxidation stage lower than that of sulfuric acid containing a sulfurcontaining group in which an --S-H group is at least reactively available.

8. A parasiticidal composition comprising thiodiphenylamine stabilized. by a hydrosulfite.

9. A parasiticidal composition comprising thiodiphenylamine stabilized by a mercaptobenzothiazole.

10. A parasiticidal composition comprising thio-diphenylamine stabilized by a thiourea.

11. A parasiticidal composition comprising thio-diphenylamine stabilized by sodium hydrosulflte.

EUCLID W. BOUSQUET. 

